Perhaps this could be moved to the library after it has run its course as an active thread. If the thread is deemed worthwhile to go into the library I would prefer to up load the images onto koiphen rather than leave them on my freeserve page. I know I can up load them via 'attachment' but I have the impression I then loose control of where in the post the images appear. Is that correct and if so who do I upload them to specific points in the post.
I am told that the message of this post is not clear, so here it is before you get lost in detail.
A GFI will only trip if there is a function ground circuit connected to the device or pond etc.
Recently there have been what I would regard as a few misleading posts about electrical safety around the pond. Before these I had said I would do an 'experiment' to demonstrate some points, well I finally got off my rear end and did the experiments.
DO NOT ATTEMPT TO RECREATE THE EXPERIMENTS IN THESE PHOTOS UNLESS YOU KNOW WHAT YOU ARE DOING.
It would actually be useful if someone Stateside who DOES KNOW WHAT THEY ARE DOING did recreate them with a US spec GFI, I think your 'lightest' trip is 5mA, whereas ours, as far as I know, is 30mA and the one used in this experiment is a '30mA' trip. I actually checked it a while a go and from memory it trips somewhere around 25mA, which is good.
You should note I am wearing two layers of latex gloves and on my feet all through the experiment wearing rubber wellies.
Ok
Photo 1) the apparatus, insepection lamp on, a plastic bucket, to simulate the pond liner, full of pond water
an inspection lamp to show that the power is there
suitable extension cables
The power comes from the cable with the black socket and the opened plug, the extension that starts with the open plug ends in the white socket and the socket feeds the inspection lamp.
Photo 2) the earth/ground wire in the open sockey has been disconnected, sorry it is blurred I didnt realise the camera had focused on the meter rather than the plug. This mean that the inspection lamp is unearthed/ungrounded.
Photo 3) the white plug and socket in the bucket of pond water with the light still lit, note no RCD/GFI protection at the moment on the inspection lamp
Photo 4) plug and socket in the water, lamp lit and meter showing the voltage between the water 4 or 5 inches from the live/hot socket and electrical earth/ground. 121.5V. Note the supply voltage was around 238V during this experiment.
Photo 5) RCD/GFI added BUT the earth/ground to the lamp is STILL disconnected, the 2nd meter is showing the voltage between the water and the acual wet soil under the bucket 118V, I cant read the other meter, sorry
It doesnt show very well but the lamp is still fully lit, IE, THE RCD/GFI DID NOT TRIP!!!!!!!!!!!!!!!!!!!!!
The above is the situation present with a faulty two wire device with no grounding of the water EVEN IF A GFI IS PRESENT
Photo 6) a clear shot of the voltages between the water and electrical earth/ground and between the water and the soil
As soon as I touched the disconnected earth/ground wire to is pin the RCD/GFI tripped, ie the electrical earth/ground from the lamp carried some of the current otherwise destined for the neutral and thereby creating a 25mA+ difference between the current flowing in the live/hot and neutral circuits within the RCD/GFI and tripping the RCD/GFI